An Iowa-based company will continue to supply Hawaiian Electric Co. with biodiesel for the utility’s 110-megawatt generating plant in Campbell Industrial Park under an agreement announced today.

Renewable Energy Group will provide three to seven million gallons of biodiesel annually for three years. The biodiesel is made from cooking oil and waste animal fat. REG’s current biodiesel contract with HECO expires at the end of this year.

REG outbid other suppliers to win the contract extension. Terms of the contract, which was submitted to state regulators for approval, were not disclosed.

The Campell Industrial Park plant is the first utility-scale combustion turbine run entirely on biodiesel.

HECO Executive Vice President Robbie Alm said biofuel is part of the company’s goal of generating 40 percent of its electricity from non-fossil fuel sources by 2030.